copending applications, Ser. Nos. 851,488 and 3,256 disclose that alkyladamantanes and/or alkyladamantanols of the C.sub.12 -C.sub.19 range containing 1-3 alkyl groups of the C.sub.1 -C.sub.3 range can be converted to hydrocarbon dimers in which two adamantane nuclei are linked to each other through an alkylene radical derived from and having the same number of carbon atoms as an alkyl group of the starting material. The reaction is effected by contacting the starting material with sulfuric acid having a strength in the range of 94-102% H.sub.2 SO.sub.4 in the absence of any other reactant material. When the reactant is a dimethyladamantane or ethyldimethyladamantane or a monool corresponding thereto, ether products can also be obtained.
Copending application Ser. No. 56,680 discloses that in these other products two adamantane nuclei are joined both through an ether linkage and through a methylene or ethylene radical. Some of the linked products are oily liquids while others are normally solid. Usually a small amount of alkyladamantanone is formed. All of these applications disclose that both the hydrocarbon dimers and ethers have high traction coefficients and are particularly useful as a component of traction fluids.
Friction or traction drive systems for the transmission of power and testing equipment for determination of the traction coefficient have been described in numerous prior art references. See for example, the following:
1. Rounds, U.S. Pat. No. 3,394,603 dated July 30, 1968 PA1 2. Hammann and Schisla, U.S. Pat. No. 3,411,369 dated Nov. 19, 1968 PA1 3. Hammann and Schisla, U.S. Pat. No. 3,440,894 dated Apr. 29, 1969 PA1 4. F.G. Rounds, J. OF CHEM. AND ENG. DATA Vol. 5, No. 4, pps. 499-507 (Oct. 1960) PA1 5. Hewko, Rounds and Scott, Proceeding of the Symposium on Rolling Contact Phenomena, pps. 157-185, Elsevier Publishing Co., Amsterdam (1962) PA1 6. Almen, J. O., U.S. Pat. No. 2,045,555 PA1 7. Hewko, Roller Traction Drive Unit for Extremely Quiet Power Transmission, AIAA Paper 67-429 PA1 A. a tractant comprising a hydrocarbon dimer of an alkyladamantane and/or alkyladamantanol of the C.sub.12 -C.sub.19 range containing 1-3 alkyl groups of the C.sub.1 -C.sub.3 range, the dimer containing two adamantane nuclei which are linked to each other through an alkylene radical derived from and having the same number of carbon atoms as an alkyl group of the starting material; and PA1 B. an ether analogous to a hydrocarbon dimer from group (A) but in which there are two linkages between nuclei, one being an oxymethylene or oxyethylene radical, the other being a methylene or ethylene radical. PA1 syn-4-(3,5-dimethyl-1-adamantyl)methyl-1-methyladamantane PA1 anti-4-(3,5-dimethyl-1-adamantyl)methyl-1-methyladamantane PA1 1-(3-methyladamantyl-1)-2-(3'-methyl-5'-ethyladamantyl-1')ethane PA1 1,2-bis(3-methyladamantyl-1)ethane PA1 1,2-bis(3-methyl-5-ethyladamantyl-1)ethane PA1 5,7-dimethyladamantanone-2 PA1 1,5-dimethyladamantanone-2 PA1 1.3-dimethyladamantanone-2
The previously cited cited copending parent application Ser. No. 679,801, filed Nov. 1, 1967 is directed generically to the use of adamantane compounds as traction fluids or as components of traction fluids.